gnat_ugn.texi: Document -gnatw.y/-gnatw.Y.

gnat_ugn.texi: Document -gnatw.y/-gnatw.Y.

2013-10-17  Robert Dewar  <dewar@adacore.com>

	* gnat_ugn.texi: Document -gnatw.y/-gnatw.Y.
	* opt.ads (List_Body_Required_Info): New flag.
	* prep.adb: Minor reformatting.
	* sem_ch7.adb (Unit_Requires_Body_Info): New
	procedure (Analyze_Package_Specification): Add call to
	Unit_Requires_Body_Info.
	* ug_words: Add entries for -gnatw.y and -gnatw.Y.
	* usage.adb: Add line for new warning switch -gnatw.y/.Y.
	* vms_data.ads: Add entry for [NO_]WHY_SPEC_NEEDS_BODY warning
	qualifier.
	* warnsw.ads, warnsw.adb: Implement new warning switch -gnatw.y/.Y.

From-SVN: r203748